1. Field of the Invention
The present invention relates to the field of hosting application services. More specifically, the present invention relates to the issue of concurrently hosting application services with multiple versions of the hosting services.
2. Background Information
With advances in integrated circuit, microprocessor, networking and communication technologies, increasing number of devices, in particular, digital computing devices, are being networked together. Devices are often first coupled to a local area network, such as an Ethernet based office/home network. In turn the local area networks are interconnected together through wide area networks, such as ATM networks, Frame Relays, and the like. Of particular notoriety is the TCP/IP based global inter-networks, the Internet.
As a result this trend of increased connectivity, increasing number of applications that are network dependent are being deployed. Examples of these network dependent applications include but are not limited to, email, net-based telephony, world wide web and various types of e-commerce. Further, increasing number of software applications that were traditionally licensed or distributed through discrete distribution medium, such as diskettes, CDROMs and the like, are being distributed online or offered as web based applications, through private intranets or public networks like the Internet.
The increased popularity of network based applications and offering of traditional software applications as application services have in turn led to the emergence of application service providers who host application services for their developers, to relieve the developers from having to maintain and operate the underlying infrastructure. To differentiate from one another, application service providers may offer hosting services or hosting runtime supports that offer functionality, usability or performance improvements over their competitors.
Thus, just like any traditional system and subsystem software developers, application service providers have a need to continually upgrade and enhance their hosting runtime services. Likewise, just like any traditional system and subsystem software, the upgrades and enhancements could have significant impact on the application services they host or support. In fact, the impact of upgrades or enhancements to the hosting service runtime support potentially could be more profound than traditional system or subsystem software. In the case of traditional system/subsystem software, generally not all licensees upgrade their system at the same time. As a result, they tend to impact the earlier adopters only. However, in the case of application service providers, once the upgrades or enhancements are promoted, all hosted application services (and their millions of users) are immediately impacted. Thus, it is desirable for application service providers to provide concurrent support for multiple versions of its hosting services or runtime support to allow gradual adoption of the new versions by the hosted application services.
However, offering concurrent support of multiple versions is not simply a matter of making the various versions available. Preferably, the concurrent support is provided in a transparent manner to the hosted applications, automatically employing the appropriate version of hosting services/runtime support. Further, as time goes on, the multiplicity of versions would inevitably become a significant burden to the application service providers, and resources become inefficiently utilized. For example, only a handful of infrequently used application services may still require the earlier versions of the runtime services. Thus, to treat all versions equally, in terms of initialization, resource allocations and like, would be extremely costly and inefficient.
Accordingly, a new approach to hosting application services, and operating the resources of an application service provision apparatus to facilitate multi-version hosting of application services is needed.